Server supervisor on GAE

app.yaml

application: ****your app name****
version: 1
runtime: python
api_version: 1

handlers:
- url: /.*
  script: main.py

main.py

import cgi
import datetime
import urllib
import wsgiref.handlers

from google.appengine.ext import db
from google.appengine.api import users
from google.appengine.ext import webapp
from google.appengine.ext.webapp.util import run_wsgi_app

from datetime import datetime

######################################### functions ###########################################
def xstr(s):
    """NUll stringifying function"""
    if s is None:
        return ''
    return str(s).encode("iso-8859-15", "xmlcharrefreplace")

def pretty_date(time=False):
    """
    Get a datetime object or a int() Epoch timestamp and return a
    pretty string like 'an hour ago', 'Yesterday', '3 months ago',
    'just now', etc
    """
    
    now = datetime.now()
    if type(time) is int:
        diff = now - datetime.fromtimestamp(time)
    elif isinstance(time,datetime):
        diff = now - time 
    elif not time:
        diff = now - now
    second_diff = diff.seconds
    day_diff = diff.days
    
    if day_diff < 0:
        return ''
    
    if day_diff == 0:
        if second_diff < 10:
            return "just now"
        if second_diff < 60:
            return str(second_diff) + " sec ago"
        if second_diff < 120:
            return  "min ago"
        if second_diff < 3600:
            return str( second_diff / 60 ) + " mins ago"
        if second_diff < 7200:
            return "hour ago"
        if second_diff < 86400:
            return str( second_diff / 3600 ) + " hrs ago"
    if day_diff == 1:
        return "Yesterday"
    if day_diff < 7:
        return str(day_diff) + " days ago"
    if day_diff < 31:
        return str(day_diff/7) + " weeks ago"
    if day_diff < 365:
        return str(day_diff/30) + " months ago"
    return str(day_diff/365) + " years ago"


def dfColorizer(s):
  """colorizes df output"""
  elements = s.split()
  outarr = []
  color="#000"
  hasDfPercent = None
  for el in elements:
    if el == None:
      pass
    elif el.find("%") != -1:
      percent = float(el.split("%")[0])
      hasDfPercent = percent
      if percent > 95:
        color="FF0000"
      elif percent > 90:
        color="FF6600"
      elif percent > 70:
        color="996600"
      else:
        color="006600"
      outarr.append("<span style='font-size:1.7em;font-weight:bold;'><br>%s<br></span>" % (el))
    else:
      outarr.append("<span style='font-size:0.9em'>" + el + "</span>")
      
  
  out = ("<font color='#%s'>%s</font>") % (color," ".join(outarr))
  if hasDfPercent >= 0 and hasDfPercent <=100:
    out = out + "<br>" 
    out = out + "<img src='http://chart.apis.google.com/chart?chbh=a,0&chs=150x20&cht=bhs&chco=%s,ffffff&chd=t:%s|100&chf=bg,s,00000000'>" % (color,percent)
      
  return out
  

def timeToColor(time=False):
  """color for _last seen_ time"""
  now = datetime.now()
  if type(time) is int:
      diff = now - datetime.fromtimestamp(time)
  elif isinstance(time,datetime):
      diff = now - time 
  elif not time:
      diff = now - now
  second_diff = diff.seconds
  day_diff = diff.days
  
  if day_diff < 0:
      return ''
  
  if day_diff == 0:
      if second_diff < 600:
          return "#00ca00"
      if second_diff < 3600:
          return "#006600"
      if second_diff < 7200:
          return "#bd7400"
      if second_diff < 86400:
          return "#ff0000"
  if day_diff == 1:
      return "#ff0000"
  if day_diff < 7:
      return "#ff0000"
  if day_diff < 31:
      return "#000"
  #if day_diff < 365:
  #    return str(day_diff/30) + " months ago"
  return "#000"
      

######################################### model ###########################################
class Status(db.Model):
    """Models an individual Guestbook entry with an author, content, and date."""
    reportdate = db.DateTimeProperty(auto_now_add=True)
    servername = db.StringProperty()
    uptime = db.StringProperty(indexed=False)
    freesysdisk = db.StringProperty(multiline=True,indexed=False)
    freedatadisk1 = db.StringProperty(multiline=True,indexed=False)
    freedatadisk2 = db.StringProperty(multiline=True,indexed=False)	
    pyserverdate = db.DateTimeProperty(indexed=False)
    serverdate = db.StringProperty(indexed=False)
    freemem = db.StringProperty(multiline=True, indexed=False)
    apache = db.StringProperty(indexed=False)
    php = db.StringProperty(indexed=False)
    mysql = db.StringProperty(indexed=False)
    load = db.StringProperty(indexed=False)
    fullreport = db.TextProperty(indexed=False)

class UniqueServer(db.Model):
    servername = db.StringProperty()

######################################### Index ###########################################
class Index(webapp.RequestHandler):
  def get(self):
    self.response.out.write('Coming soon')

######################################### Showing status ###########################################
class ListStatuses(webapp.RequestHandler):
  def get(self):
    
    self.response.out.write("<html><head>"
                            "<style>body{font-family:arial,helvetica;background-color:#444;}"
                            "th{color:#bbb;background-color:black;}"
                            "td{background-color:#ccc;}"
                            "h1{color:#ccc;}"
                            "</style>"
                            "</head>"
                            "<body>"
                            "<h1>Dashboard</h1><br />");    
    
    self.response.out.write("<table border=1 cellspacing=0 cellpadding=4><tr>"
                            "<th>Name</th>"
                            "<th>Last seen</th>"
                            "<th>Sys disk</th>"
                            "<th>Data disk 1</th>"
                            "<th>Data disk 2</th>"
                            "<th>Uptime</th>"
                            "<th>Time lag</th>"
                            "<th>Load</th>"
                            "<th>Free mem</th>"
                            "<th>Apache</th>"
                            "<th>PHP</th>"
                            "<th>MySql</th>"
                            "<th>Full report</th>"
                            "</tr>");
                            
    
    #find all servers ======================================
    servers = db.GqlQuery("SELECT * FROM UniqueServer ORDER BY servername ASC")
    for server in servers:
      #find last status =====================================
      statuses = db.GqlQuery("SELECT * FROM Status WHERE servername = '%s'"
                            "ORDER BY reportdate DESC LIMIT 1" % server.servername)
      
      for s in statuses:
        #get delta t =======================================
        if s.pyserverdate == None or s.reportdate == None:
          lag = "-"
        else:
          t1 = s.pyserverdate
          t2 = s.reportdate
          if t1 > t2:
            delta = -(t1-t2).seconds
          else:
            delta = (t2-t1).seconds
          lag = str(delta) + " s"
        
        #print table row ===================================
        
        self.response.out.write("<tr>"
                                "<td style='background-color:%s;'>%s&nbsp;</td>"   #name
                                "<td title='%s' style='background-color:%s;'>%s&nbsp;</td>"   #last seen
                                "<td>%s&nbsp;</td>"   #free sys disk
                                "<td>%s&nbsp;</td>"   #free data disk1
                                "<td>%s&nbsp;</td>"   #free data disk2
                                "<td>%s&nbsp;</td>"   #uptime
                                "<td title='%s'>%s&nbsp;</td>"   #system date lag
                                "<td>%s&nbsp;</td>"   #load
                                "<td>%s&nbsp;</td>"   #free mem
                                "<td>%s&nbsp;</td>"   #apache
                                "<td>%s&nbsp;</td>"   #PHP
                                "<td>%s&nbsp;</td>"   #Mysql
                                "<td title='%s'>...</td>"   #Full report
                                "</tr>" % (
                                timeToColor(s.reportdate), xstr(s.servername), 
                                xstr(s.reportdate), timeToColor(s.reportdate) ,pretty_date(s.reportdate), 
                                dfColorizer(xstr(s.freesysdisk)),
                                dfColorizer(xstr(s.freedatadisk1)),
                                dfColorizer(xstr(s.freedatadisk2)),
                                xstr(s.uptime),
                                xstr(s.serverdate),
                                xstr(lag),
                                xstr(s.load),
                                xstr(s.freemem),
                                xstr(s.apache),
                                xstr(s.php),
                                xstr(s.mysql),
                                xstr(s.fullreport).replace("'",'"'))
                                );
    
    #close table =============================================
    self.response.out.write('</table></body></html>');


######################################### POSTING DATA ###########################################
class PostStatus(webapp.RequestHandler):
  """Handle incoming requests and save to database"""
  
  def post(self):
    #get and validate server name ==================
    cursrvname = self.request.get('servername')
    
    if cursrvname == None:
      return
      
      
    #store server to table of servers  ==============      
    result = db.GqlQuery("SELECT * FROM UniqueServer WHERE servername = '%s'" % cursrvname)
    if result.count() == 0:
      newsrv = UniqueServer()
      newsrv.servername = cursrvname
      newsrv.put()
    
    #store status ==================================
    s = Status()
    s.servername = cursrvname    
    s.freesysdisk = self.request.get('freesysdisk') or None
    s.freedatadisk1 = self.request.get('freedatadisk1') or None
    s.freedatadisk2 = self.request.get('freedatadisk2') or None
    s.uptime = self.request.get('uptime') or None
    s.serverdate = self.request.get('serverdate') or None
    s.freemem = self.request.get('freemem') or None
    s.apache = self.request.get('apache') or None    
    s.php = self.request.get('php') or None
    s.mysql = self.request.get('mysql') or None
    s.load = self.request.get('load') or None
    s.fullreport = self.request.get('fullreport') or None
    
    if self.request.get('pyserverdate'):
      s.pyserverdate = datetime.strptime(self.request.get('pyserverdate'),"%Y-%m-%d %H:%M:%S")
    s.put()
    self.response.out.write('ok')
  
  
  def get(self):
    self.post()
    
    
######################################### Housekeeping ###########################################
application = webapp.WSGIApplication([
  ('/', Index),
  ('/showstatus', ListStatuses),  
  ('/post', PostStatus)
], debug=True)


def main():
  run_wsgi_app(application)


if __name__ == '__main__':
  main()